DIESEL TRUCK engine Marinization

Ask any submariner about what happens when surfacing and you'll hear a lot of cursing and opinions contrary to yours.

 

From what I have seen the new electronic marine diesels are incredibly fuel efficient, whereas the old mechanical governed motors drink fuel.

The middle of the ocean is not the place to find out how reliable your engine is, especially if you only have one of them.

That said, a boat engine requires some special parts, which are expensive if bought separate.

Lastly the government inspector that does the inspection to license your boat , might just totally refuse to accept a home made engine installation, unless it is signed off by a marine engineer.

 

Conversion Engine

Lastly the government inspector that does the inspection to license your boat , might just totally refuse to accept a home made engine installation, unless it is signed off by a marine engineer.[/QUOTE]


Happily here in the USA there is NO inspection (as you describe ) unless you wish to carry more than 6 passengers FOR HIRE.

Having a hull constructed , and fitting it out as desired is not a government matter.

On a diesel the main difference between a store bought "Marine" engine and every other iteration of the same engine is a wet exhaust manifold.

Exhaust manifolds are not free , but there a load cheaper than the same 25 year old block painted "Marine".With a dry stack and keel cooling no special Marine pumps and coolers would be required .(Perhaps for the tranny)

With a modest goal of 12 to 14K ocean cruising (on about 3 to 4 GPH) the engine will hardly be stressed overmuch.

A dash at top speed (what ever it ends up ) would be at 15 to 20GPH , so wouldn't fit my exchecker very well.

FAST FRED

 

In the USA there is a blanket regulation that allows the USCG or any other marine authority to stop a unsafe vessel. Also, there are regulations for machinery, fuel, floatation, lights, safety equipment,etc.

 

AM well aware of the requirements of USCG Subchapter "T",
as we have constructed over a dozen boats to that spec.

There is NOTHING about a marinized block be it truck ,"Marine" , or Ex Lawn tractor that does not pass the far higher (than mere yacht) scrutiny on boats that carry 49 Pax, for hire.

The USCG "unsafe " bit is to stop the need for SAR and rescues of folks wishing to sail Round the World in bathtubs.

FAST FRED

 

You say:"There is NOTHING about a marinized block be it truck ,"Marine" , or Ex Lawn tractor that does not pass the far higher (than mere yacht) scrutiny on boats that carry 49 Pax, for hire." How about flame arrestors, fuel pumps and electrics?

 

You have confused the requirements for GASOLENE engines with the far less demanding requirements of a diesel vessel.(even for commercial service)

Flame arrestors ect are useless on diesels ,
and there is NO need for "Spark proof" electrics.

Good "workmanship " such as large enough engine mounts ,
or the use of "Proper" fuel lines is required, but very EZ to do.

FAST FRED

 

I thought you said any block, including gas.

 

Marine transmissions contain very strong end bearings which can sustain propeller push as well as occasional pull or unbalance of the shaft. Car or truck transmissions have much lighter end bearings. You can use instead an oversize-preferably stainless push-type bearing if you can do some special machining of the shaft. Point is you will then need to connect your non-marine transmission to the shaft, transmitting the movement but not the constrains. This might be tricky or expensive ("Acquadrive"). Also, I understand than DIY engine marinisations and truck transmissions might not be as reliable as an expensive OTS marine product. So why not use fairly simple stuff with twin independant engines and screws ?. Most likely, "global" reliability (that is : at least one engine up and running) should be ways above one single OTS engine for much cheaper.

 

You mention( Aquadrive) Lda,do you have any website information,my infomation is mostly pre-internet.I would like to up-date if you can help.

 

I found it there (in French) :

http://www.infanger-propeller.ch/fr/index.php?page_id=12

possibly in New Zealand, it be easier to look for Python-Drive which looks similar, there:

http://www.pyiinc.com

 

Hi,

Can someone tell me why a 350HP python drive unit costs around 3.500,00USD ????

It are just some thrustbearings joints and stainless steel machined parts, or im I wrong?

Greetz,

Daniel

 

The "price" of most products include the cost of refining the idea (R&D) and building and testing many prototypes.

Not merly the production cost, overhead ,marketing and paying for all the silly Gov imposed rulles .

When an item is virtually a One OF , its always expensive.

FAST FRED

 

I guess that quite a few people just don't mind...
Those who are good at mechanics will understand that you can get very similar results with an industrial stainless push-type bearing and an universal joint, provided the bearing is rigidly attached to the engine (they can be installed on a common suspended framework...)
I don't know if people who are not part of any of those groups are numerous enough to form a market....

 

If you have a good truck motor,why not fit it up as close as possible to the design as intended for a truck,which would be as reliable an installation as you could get,and easiest maintenance.Use original radiator,fan and waterpump ( with suplementary linear heat exchanger inside the boat or keel cooler),clutch gearbox,(choose prop to suit either first two gears or direct drive) original engine mountings (use chain for capsize mountings).Insulate original or water jacket exhaust manifold but inject raw water where exhaust tailpipe flange meets manifould.(exhaust pulses will help cool manifold) or just insulate.Install a raw water pump to pump raw water through linear heat exchanger,around original oil filter,or oilpan cooling(flexable tubing) then some to cool shaft gland and the rest of the water inject into exhaust tailpipe.With a good engine cover designed to flow air around motor and out of the hull(extra extractor fan maybe).Install motor related electronics on engine cover for easy maintanance,with seperate wiring loom for boat electrics.Linear heat exchanger will give extra water to cooling system and maintain good reliable cooling,(with over heating the killer of most boat engines).Run heated engine water from the back of the motor head (original heater lines) to heat the cabin for comfort.Use this line to carry heated water through linear heat exchanger back to motor through water pump.Twin universal joints with a sliding spline fitted to propshaft supported by a SKF FY type adjustable thrust bearing will give you 10 degrees of angle on motor and up to 10 degrees of prop shaft angle.Total 20 degrees.Big outboards have no fan cooled covers and they work hard and well.Motor should run like they do in a truck.